Ever since the introduction of Windows Vista in early 2007, Microsoft has enforced the rule that Windows drivers must carry digital signatures by default. Any software that runs in kernel mode, in fact, has to be signed by the company. This is a security measure that should prevent malicious software from digging its claws in too deep. However, what happens when Microsoft gives its blessing to a rootkit? That's what happened a few months ago and was just now discovered thanks to G DATA Software security analyst Karsten Hahn. Initially, the company received a false-positive alert from a driver that...